The present invention relates to an improved suction device used to collect body fluids.
Modern medical practice commonly uses suction devices to improve drainage of fluids from the body of a patient. For example, suction devices are routinely used to speed wound drainage following surgery. One type of wound suction device includes a portable, relatively small suction chamber which is coupled to a source of body fluids. Typically, such chambers are repeatedly charged with a vacuum, filled with body fluids, and then drained during the course of a single drainage treatment. U.S. Pat. Nos. 3,889,677 and 3,779,243 disclose two such portable suction devices.
A potential drawback of many such devices is that it is often difficult to determine from a distance whether the device is developing proper suction. Generally, a portable suction device of the type described above will lose suction when it becomes filled. Unless the loss of suction is promptly noticed and the chamber is emptied to restore suction, proper drainage may be interrupted.
Another potential drawback of many prior art devices relates to the amount of suction developed at various stages in the use of the suction device. Preferably, a suction device should develop a uniform suction throughout its fill cycle, rather than a higher suction when the device is empty and a progressively lower suction as the device fills.
A third drawback of the prior art relates to the contaminaion of suction devices in use. As explained above, it is customary to fill and empty a suction device repeatedly during a single drainage treatment. Conventional drainage devices must be opened to be drained, and they can therefore become contaminated during use. This contamination can then spread to the patient when drainage is resumed.